1. Field of the Invention
The present invention relates to an object detection device and a sensing apparatus, and more specifically to an object detection device a detection target of which is an object, and a sensing apparatus that includes the object detection device.
2. Description of the Related Art
In recent years, an object detection device to detect presence or absence of an object or distance to the object has been developed actively.
For example, in Japanese Laid-open Patent Publication No. 2010-096574, a laser radar is disclosed that includes a light projection unit that emits laser beams, a scanning unit that two-dimensionally scans laser beams emitted from this light projection unit, a control unit that issues a projection instruction of laser beams to the light projection unit and that controls scanning by the scanning unit, a selecting unit that selects only a reflection laser beam that reflects on and returns from a measurement target by laser beam scanning by the scanning unit, based on an instruction from the control unit, a light receiving unit that receives the reflection laser beam selected by this selecting unit, and a distance calculating unit that acquires distance information of the measurement target based on light emission timing of a laser beam given by the control unit and on light reception timing of the reflection laser beam given by the light receiving unit.
Moreover, in Japanese Patent No. 2894055, a laser radar device that is mounted on a vehicle and that determines whether an obstacle is present based on reflection light from an object of laser beams that are sent to space forward in a direction of travel is disclosed that includes a light sending unit that sends laser beams to a visual field forward in the direction of travel of the vehicle, a light receiving unit that has a reception optical system receiving reflection laser beams from the visual field, that divides the visual field into three or more in a horizontal direction as light-receiving visual fields, and that performs processing such as electric conversion, amplification, and digitalization of reflection laser beams collected by the reception optical system independently for each of the divided visual fields, and a signal processing unit that chronologically processes each output of the light receiving unit in predetermined sequence, and that performs determination of presence or absence of an obstacle in each of the visual fields, measurement of distance to an obstacle, and chronological monitoring of movement of an obstacle in each of the divided visual fields.
Furthermore, in Japanese Patent No. 3446466, a reflection measuring device is disclosed that includes a rotation polygon mirror having multiple reflection surfaces with various inclination angles relative to a rotation axis, a light source that generates pulsed light, a pulsed-light entering unit that cause the pulsed light to enter the rotation polygon mirror from a predetermined direction, and a light receiving unit that receives pulsed light emitted from a reflection surface of the rotation polygon mirror to a forward measuring area and returned from an object in the measuring area.
However, in conventional devices, it has been difficult to achieve both improvement of detection resolution and increase of life of a light source.